[llvm] [AMDGPU] Improve the description of asyncmark semantics (PR #202579)

[Pierre van Houtryve via llvm-commits]

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@@ -10,21 +10,18 @@
 Introduction
 ============
 
-Asynchronous operations are memory transfers (usually between the global memory
-and LDS) that are completed independently at an unspecified scope. A thread that
-requests one or more asynchronous transfers can use *asyncmarks* to track
-their completion. The thread waits for each asyncmark to be *completed*, which
-indicates that requests initiated in *program-order* before this asyncmark have also
-completed.
+Asynchronous operations are operations that are completed independently at an
+unspecified scope. A thread that requests one or more async operations can use
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Pierre-vh wrote:

+1 for unambiguous terms. I think "issue" is best because it matches HW terminology

https://github.com/llvm/llvm-project/pull/202579